E-Storegeneral term of a sequence having differences in A.P.>>>an easier way..and conceptual
i read sneha's article for this ques. so these are the line from her article....""
I saw a question regarding a sequence 2, 7, 14, 23, 34......
the person was asking for the 99th term. I thought the way of finding general term of such sequence is helpful for we all. so here is a shortcut for such problems.""
i have another way to solve it apart from sneha.you have have to think about it.
you see that common difference is coming out to be in a.p. now relise that
difference between first and nth tem is equal to sum of the common diffrence b/t them...ok!! you may take simpler examples.
so just we find sum of the common differences (5+7+11+...till n-1 terms) and
nth term - first term = sum calculated.
for example. sequence is 2 7 14 23...
we have to calculate 99 th term then lets see what the series of c.d. coming thats 5,7,9,11.....
now take sum of the 98 terms bcoz there are 98 terms of common diffrence bt 99 terms. got it!
thats coming out to be 9996. now appling the formula
nth term-2=9996..........getting 9998 as ans...
.its my own language so if you cant understand this. please tell me i ll try to make it simpler. its very easy and effective so you should know it..thank you
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